About Us

Our Story

Sio Capital is a global equity market neutral healthcare hedge fund. Headquartered in New York, Sio Capital is a SEC-registered investment advisor that was founded by Dr. Michael Castor in 2006.  

Sio Capital takes a balanced approach to investing, with an eye toward both capital growth and capital preservation. The investment team, comprised of six seasoned analysts, recognizes that every investment has risk. Our principle goal is to find investments with low risk and outsized upside potential returns. We expect to deliver on the goal of generating returns in both up and down markets, with a combination of prudent stock selection and by betting against overvalued stocks that have a likelihood of near term negative surprises. These latter “short” investments are expected to deliver returns on their own and they differentially protect our investment portfolio during market downturns. 

Sio Capital focuses on healthcare. The landscape is large, diverse and heterogeneous. It includes companies in such sectors as insurance, biotech, medical devices, pharmaceuticals, hospitals, service companies and more. Investing in healthcare requires specialized knowledge of science, industry dynamics, intellectual property law and regulatory issues. The complexity of these factors often creates mispricing of stocks and investment opportunities. Sio focuses on recognizing and understanding these issues all day, every day so that we are able to capitalize on opportunities as they arise.

Sio’s rigorous approach to identifying investments, coupled with a structured process of portfolio oversight and risk mitigation, has been our foundation for successfully generating returns over time.